Calculating conception date

Patient: Good day, my period started on February 20th (my period cycle is 28 days) On the 28th of February I had unprotected sex after 40 hours I took Escapelle pill. On March 17th, I had sex again, with my ex, but he did not ejaculate inside me. On March 22nd I got my period (1-2 days late). I hope it was a period, not just bleeding after EC pill. On March 29-30 I had sex with my boyfriend. On April 28th I find out I am 5-6 weeks pregnant (baby’s CLR 3mm transvaginal ultrasound). On April 30th I did one more transvaginal ultrasound (CLR 4,9mm) and doctor sad I am 6weeks and 1 day). On June 10th I was 12weeks 4 days (baby’s CRL 60mm). On June 18th I was 13 weeks and 5 days (CRL 83 mm, BPD 28 mm). On August 11 I was 21 weeks 4 days. Please tell me, is it possible I may have conceived this baby because of the sex I had with my ex on March 17th? I read that taking EC delays ovulation and mess up all your cycle. Thank You!!!

Doctor: It is most likely that you conceived in March as your first scan in April mentioned a gestational age of 4- 5 weeks. As gestational age of the baby is calculated from he last menstrual period and you had a period in March it is unlikely that any intercourse in February could’ve resulted in a pregnancy.Having said that, paternity is a very sensitive issue and determines the future of your unborn child. If you have any doubts about who the father of the child is, it is best that you mention the same to your OBGYN doctor who shall be able to refer you to a paternity testing center. Paternity testing can be done antenatally before the baby is born by many methods. Invasive methods such as chorion villus biopsy, amniocentesis as well as non invasive tests using the free fetal DNA in the mothers blood are the options available to you. In most places, you need to let your doctor well in advance about your doubts, so that you may have the verdict by the time the baby arrives.It would be best that you do not delay this issue and get things sorted out.

Dr. Suneel Sharman M.D.

Dr. Suneel Sharman completed his residency in Family Medicine at the University of Toronto. He currently operates Infinity Health Centre, a walk-in-clinic in downtown Toronto.